Castles and Crusades is probably even MORE compatible with 5e stuff than it was with 3e, 3.5, Pathfinder, or AD&D!
Part of that is probably because 5e (some would claim they just ripped it off of C&C) uses a very similar dynamic as C&C with it's skill challenges and the variable range (bounded accuracy) in regards to skills being basically the same (+2 to +6 bonuses).
Except for Warriors (which still get that +1 per level to attack bonuses...which I actually feel work better with how a Warrior SHOULD hit in a game compared to those who aren't trained warriors) other classes ALSO have comparable hit bonuses similar to 5e as well, which makes it very easy to be compatible with 5e (more than many other of the listed systems).
Just recently have been HEAVILY considering running PF Abomination Vaults (the version giggles for 5e) using C&C rules. Haven't made up my mind on that yet, but considering it as C&C is simpler so you get that itch, but more compatible than some of the other ones which are also simple in style.